Multi-stage storm drain filter insert

ABSTRACT

A multi-stage drain filter insert ( 10 ) comprises a first basket ( 14 ) installed in a drain (D) inlet (I). A second basket ( 20 ) fits inside the first basket and is installed therewith for debris in the water flowing into the insert to be collected in a bottom of the second basket. An absorption media in a pouch ( 26 ) installed in the second basket for removes hydrocarbons from water flowing into the drain through the insert. A filtration media in a pillow ( 24 ) installed in the first basket between the first and second baskets removes contaminants, including bacteria, from water flowing through the second basket into the first basket. As a result, debris and contaminants are substantially removed from water flowing from the insert into the drain.

CROSS REFERENCE TO RELATED APPLICATIONS

Provisional patent application 61/305,341 filed Feb. 17, 2011.

STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT

N/A

BACKGROUND OF THE INVENTION

This invention relates to drain filters; and, more particularly tomulti-stage storm drain filter inserts.

It is well-known that, over time, drains used for the disposal of rainwater, for example, can become clogged with dirt and other debriscarried by the water into the drain. Besides the resulting blockage, theclogged site can become a breeding ground for bacteria. To prevent theseproblems, filters have been installed in drains to trap the dirt,sediment, and other debris. This then allows the water to flow freelyinto and through the drain. Further, by periodically cleaning orreplacing the filter, the chances of bacteria breeding at the site aresignificantly reduced if not eliminated altogether.

The present invention is directed at a multi-stage storm drain filterwhich is more effective than current filters in trapping and retainingdebris, sediment, and other materials, significantly reduces the threatof theft of a filter, is low cost, and easy to maintain.

BRIEF SUMMARY OF THE INVENTION

The present disclosure is directed to a storm drain filter having aplurality of filter inserts for removing various pollutants flowing intoa drainage system. The filter comprises a dual stage filter whose firststage traps and retains larger debris flowing into the drain, and asecond stage which traps fine sediments and particles. An absorbentmedia pouch is installed in the first stage to absorb hydrocarbons, anda second media absorbing pouch is installed in the second stage of thefilter. The pouches include absorbent materials so that water flowinginto the drain is exposed to two levels of filtration for hydrocarbons,metals, bacteria, and other materials. The result is that substantiallyclean water enters the drain after passing through the filter.

The dual-stage filter design and installation allows more metals flowinginto a drain to be reclaimed for sale back to metal reclaimers.

The filter is low cost, and easy to install and maintain. For example,the pouches are reusable and recyclable so to lower the carbon footprintleft on the environment.

Other objects and features will be in part apparent and in part pointedout hereinafter.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

The objects of the invention are achieved as set forth in theillustrative embodiments shown in the drawings which form a part of thespecification.

FIG. 1 is a sectional view of a drain inlet for a sewer systemillustrating the dual-stage drain filter insert of the present inventionas installed;

FIG. 2 is a sectional view of the installed filter insert;

FIG. 3 is an exploded view of the filter insert; and,

FIG. 4 is a perspective view of a portion of the installation of thefilter insert.

Corresponding reference characters indicate corresponding partsthroughout the several views of the drawings.

DETAILED DESCRIPTION OF INVENTION

The following detailed description illustrates the invention by way ofexample and not by way of limitation. This description clearly enablesone skilled in the art to make and use the invention, and describesseveral embodiments, adaptations, variations, alternatives and uses ofthe invention, including what is presently believed to be the best modeof carrying out the invention. Additionally, it is to be understood thatthe invention is not limited in its application to the details ofconstruction and the arrangement of components set forth in thefollowing description or illustrated in the drawings. The invention iscapable of other embodiments and of being practiced or carried out invarious ways. Also, it will be understood that the phraseology andterminology used herein is for the purpose of description and should notbe regarded as limiting.

Referring to the drawings, a multi-stage drain filter insert of thepresent invention is indicated generally 10. Insert 10 is sized to beinstalled in the inlet I of a drain D beneath a grate G which covers theinlet. Water flow into and through drain D is indicated by the solidline arrows in FIG. 1. The drain, which empties into a drain or sewersystem is found in a variety of locations including, for example,parking lots, service stations, car washes, industrial sites,restaurants, apartments or multi-family dwellings, and subdivisions. Thewater which flows into inlet I of drain D may carry a variety ofcontaminants including such matter as dirt, rocks, vegetation, debris,hydrocarbons (e.g., oil), and metal and plastic. In addition to these,the waste water may also contain bacteria. Multi-stage insert 10 has thecapacity to remove substantial amounts, if not all, of thesecontaminants, including the bacteria, as the water flows through theinsert. The result is that the water downstream from the insert isrelatively clean.

With respect to FIGS. 1 and 4, to install insert 10 in the drain, grateG is first removed. Next, J-hooks 18 are anchored into sidewalls W ofthe drain using concrete anchor bolts inserted in holes H formed in thesidewalls. The spacing between the respective sets of holes correspondsto the width of a filtration basket 14. A basket 14 is supported inplace by support rods 12 which are inserted through sleeves 16 formedalong opposite sides of basket 14. The protruding ends of the rods aresupported on the respective J-hooks 18 so to suspend basket 14 in place.

Filtration basket 14 comprises a second stage filtration basket of draininsert 10. Fitted within basket 14, when insert 10 is installed, is afirst stage trash basket 20. Both filtration basket 14 and trash basket20 are generally rectangular in size and shape and both have a closedbottom and an open top. Basket 14 is made of a poly-nylon open-meshmaterial. Further, woven nylon webbing support straps 21 extend up eachside of basket 14 along the corners of the basket. Each strap 21 is sewninside each corner seam of basket 14. An eyelet or loop is formed at theupper end of each strap, and as shown in the drawings, the protrudingends of the support rods 12 are inserted through the eyelets to preventthe corners of basket 14 from sagging when installed in the drain.

Basket 20 has sides made of a non-woven filter fabric. The bottom of thebasket, however, is made of a woven geo-textile filter material. Basket20 further has D-rings 22 located at each corner of the upper, open endof the basket. The D-rings are attached to snap hooks 23 located at theupper corner on each side of the min filter body. See FIG. 3.

The baskets are available in a number of sizes and which size is used isdependent upon the size of the drain in which insert 10 is installed.For drains of an unconventional size, baskets 14 and 20 are custom made.

A media pillow or pouch 24 is sized to fit into the bottom of basket 20as shown in FIG. 2. As shown in FIG. 3, pillow 24 comprises a pluralityof adjoining pillow segments each of which is filled with a filter mediato absorb bacteria in the water flowing through filter insert 10. Whilesix pillow segments are shown in FIG. 3, it will be understood by thoseskilled in the art that there could be more or fewer segments withoutdeparting from the scope of the invention. Further, the media with whichpillow 24 is filled is site specific. In general, the media comprises amixture of zeolite, pearlite, and granular activated carbon (GAC)together with other media, as appropriate.

In addition to media pillow 24, hydrocarbon screen pouches 26 areinstalled in trash basket 20. This as shown in FIG. 2. The pouches 26are floatable pouches and are filled with a hydrocarbon absorbent mediaso the pouches 26 can filtering out hydrocarbons in the water flowinginto drain D and through filter insert 10. As shown in FIG. 3, twopouches 26 are fitted into basket 20, the pouches being laid crosswisein the bottom of the basket.

Installation of filter insert 10 is as follows:

First, the holes H are drilled into the sidewalls of the drain inlet.

Next, a media pillow 24 is placed in the bottom of filtration basket 14.

Then, waste basket 20 is inserted into the open end of basket 14.

After that, the support rods 12 are fitted through the sleeves 16 formedin basket 14.

The D-rings 22 and the eyelet ends of the straps 21 of basket 14 areinserted onto the protruding ends of the support rods.

Next, the ends of the support rods are installed on the J-hooks 18 so tosuspend basket 14 in the drain inlet.

Finally, the hydrocarbon absorbent pouches 26 are placed in the bottomof basket 20.

After the installation is complete, a baffle plate 28 is fitted on topof basket 14. The length and width dimensions of baffle plate 28substantially correspond to those of drain inlet I. The baffle plate hasa central, generally rectangular opening 30 in its top surface 32. Theopening is placed over the center of insert 10 and the top surface ofthe baffle plate slopes inwardly from the outer margin of the baffleplate toward the opening. Accordingly, water flowing through grate Ginto inlet I is directed into the center of insert 10 and falls directlyinto waste basket 20, onto the pouches 26, through the bottom of basket20 onto media pillow 24 and then through the bottom of filtration basket14 into drain D.

If more water flows into the filter insert 10 than can immediately flowthrough the baskets and into drain D, it will start to backup in theinsert. As it does so, the pouches 26 will float on the surface of thewater collecting in the insert. Since oil sits atop any water, thepouches 26 are filled with hydrocarbon absorbent media, the pouches nowabsorb any oil with the water. Debris such as rocks, leaves, paper, etc.are collected in the bottom of basket 20.

Pillow or pouch 24 does not float. As such, as water flows downwardlythrough basket 14, it flows through the segments comprising the pouchand contaminants, including bacteria, in the water are absorbed by themedia in pouch 24. Over time, this material will fill-up the insert,block water flow through it, and backup the drain. Accordingly, amaintenance schedule is established by which this material isperiodically collected from the insert and the pouches 26 and pillow 24are replaced with new ones. Or, after heavy rains, the maintenanceprocedure is performed as a matter of course.

In view of the above, it will be seen that the several objects andadvantages of the present disclosure have been achieved and otheradvantageous results have been obtained.

1. A multi-stage drain filter insert comprising: a first basketinstalled in a drain inlet; a second basket fitted inside the firstbasket and installed therewith for debris in the water flowing into theinsert to be collected in a bottom of the second basket; an absorptionmedia installed in the second basket for removing hydrocarbons fromwater flowing into the drain through the insert; and, a filtration mediainstalled in the first basket between the first and second baskets toremove contaminants, including bacteria, from water flowing through thesecond basket into the first basket whereby debris and contaminants aresubstantially removed from water flowing from the insert into the drain.2. The filter insert of claim 1 in which the absorption media iscontained in a pouch which floats within the second basket as the waterlevel rises so to absorb hydrocarbons floating on the top of the water.3. The filter insert of claim 2 in which the filtration media iscontained in a pouch which rests on the bottom of the second basket toremove contaminants as water flows out of the filter insert through thebottom of the second basket.
 4. The filter insert of claim 1 furtherincluding support means for supporting the first and second baskets inthe drain inlet.
 5. The filter insert of claim 1 further including abaffle sitting over the top of the second basket, the baffle having acentral opening through which water flowing into the drain inlet isdirected into the top of the first and second baskets.